Real-equivalent-time oscilloscope clock data recovery with software equalizer

A test and measurement instrument comprising:

• an input configured to receive a signal under test having a repeating pattern;
• one or more analog-to-digital converters (ADC) to sample the signal under test at a sample rate over a plurality of repeating patterns to digitize the signal to produce a sampled signal under test;
• one or more processors configured to execute code to cause the one or more processors to:
• recover a clock from the sampled signal under test;
• use the clock to generate an original pattern waveform;
• interpolate and resample from the original pattern waveform to generate an evenly time-spaced pattern waveform using the clock;
• apply an equalizer to the evenly time-spaced pattern waveform to produce an equalized pattern waveform;
• interpolate and resample from the equalized pattern waveform to produce a new waveform having equalized samples at sample times of the sampled signal under test;
• recover an updated clock from the new waveform;
• and
• use the updated clock to produce an updated waveform.